scholarly journals Spectral scaling of static pressure fluctuations in the atmospheric surface layer: The interaction between large and small scales

1998 ◽  
Vol 10 (7) ◽  
pp. 1725-1732 ◽  
Author(s):  
John D. Albertson ◽  
Gabriel G. Katul ◽  
Marc B. Parlange ◽  
William E. Eichinger
Keyword(s):  
Surface Layer ◽  
Atmospheric Surface Layer ◽  
Static Pressure ◽  
Pressure Fluctuations ◽  
Small Scales

Ground effects on pressure fluctuations in the atmospheric boundary layer

1978 ◽  
Vol 86 (3) ◽  
pp. 491-511 ◽  
Author(s):  
M. M. Gibson ◽  
B. E. Launder
Keyword(s):  
Boundary Layer ◽  
Heat Flux ◽  
Surface Layer ◽  
Atmospheric Surface Layer ◽  
Pressure Field ◽  
Pressure Fluctuations ◽  
Gravitational Effects ◽  
Fluctuating Pressure ◽  
Stratified Shear Flow ◽  
Ground Effects

Proposals are made for modelling the pressure-containing correlations which appear in the transport equations for Reynolds stress and heat flux in a simple way which accounts for gravitational effects and the modification of the fluctuating pressure field by the presence of a wall. The predicted changes in structure are shown to agree with Young's (1975) measurements in a free stratified shear flow and with the Kansas data on the atmospheric surface layer.

scholarly journals Microscale pressure fluctuations measured within the lower atmospheric boundary layer

1972 ◽  
Vol 53 (2) ◽  
pp. 351-384 ◽  
Author(s):  
J. A. Elliott
Keyword(s):  
Boundary Layer ◽  
Atmospheric Boundary Layer ◽  
Large Scale ◽  
Static Pressure ◽  
Pressure Fluctuations ◽  
Pressure Sensors ◽  
Net Energy ◽  
Velocity Fluctuations ◽  
Dominant Feature ◽  
Small Scales

Eulerian measurements of microscale fluctuations in static pressure are used, in conjunction with measurements of air velocity, to describe some of the properties of the static pressure fluctuations that occur within the turbulent flow of the lower atmospheric boundary layer. Using an instrument developed to measure the static pressure at a point within the boundary layer, data were collected at heights ranging from the surface up to about 6 m. The results are presented as power spectra, cross-spectra, coherence and phase. For all observations over a flat boundary the root-mean-square pressure produced by the boundary-layer turbulence is about 2.6 times the mean stress. The pressure spectra are found to have a, well-defined shape which does not change with height above the surface; at the higher frequencies the spectra show a power-law behaviour with a mean slope of −1·7. A number of observations with two pressure sensors are used to describe the structure and propagation velocity of individual pressure pulses.A dominant feature of the pressure-velocity relationship is that the large-scale pressure fluctuations are approximately in phase with the downstream velocity fluctuations; at small scales there is a large phase difference (∼−135°). These phase differences are interpreted to be the result of interaction of the large pressure-producing scales with the earth's surface, the small scales being ‘free’ of the surface. Prom the simultaneous measurements of pressure and downstream velocity the effect of pressure forces on the energy flux out of the downstream velocity fluctuations was evaluated. Typical values are about 0-45 of the net energy source to the downstream component. By means of pressure and vertical velocity measurements an estimate of the pressure divergence term in the net energy budget of a boundary layer is made. It was found to be about 1/10 of the energy feeding term.

Probability law of turbulent kinetic energy in the atmospheric surface layer

2021 ◽  
Vol 6 (7) ◽  
Author(s):  
Mohammad Allouche ◽  
Gabriel G. Katul ◽  
Jose D. Fuentes ◽  
Elie Bou-Zeid
Keyword(s):  
Surface Layer ◽  
Kinetic Energy ◽  
Turbulent Kinetic Energy ◽  
Atmospheric Surface Layer
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